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861.
Software and Systems Modeling - Adapting the user interface of a software system to the requirements of the context of use continues to be a major challenge, particularly when users become more...  相似文献   
862.
863.
Multimedia Tools and Applications - New mobile applications need to estimate user activities by using sensor data provided by smart wearable devices and deliver context-aware solutions to users...  相似文献   
864.
Hashemi  M. S.  Akgül  A. 《Engineering with Computers》2021,37(2):1147-1158
Engineering with Computers - In this paper, a Lie-group integrator based on $$GL_4(\mathbb {R})$$ and the reproducing kernel functions has been constructed to investigate the flow characteristics...  相似文献   
865.
Many studies have demonstrated the crucial role of vocabulary in predicting reading performance in general. More recent work has indicated that one particular facet of vocabulary (its depth) is more closely related to language comprehension, especially inferential comprehension. On this basis, we developed a training application to specifically improve vocabulary depth. The objective of this study was to test the effectiveness of a mobile application designed to improve vocabulary depth. The effectiveness of this training was examined on 3rd and 4th grade children's vocabulary (breadth and depth), decoding and comprehension performances. A randomized waiting-list control paradigm was used in which an experimental group first received the intervention during the first 4 weeks (between pretest and post-test1), thereafter, a waiting control group received the training for the next 4 weeks (between postest1 and posttest2). Results showed that the developed application led to significant improvements in terms of vocabulary depth performance, as well as a significant transfer effect to reading comprehension. However, we did not observe such a beneficial effect on either vocabulary breadth or written word identification. These results are discussed in terms of the links between vocabulary depth and comprehension, and the opportunities the app presents for remedying language comprehension deficits in children.  相似文献   
866.

The paper proposes a novel metaheuristic based on integrating chaotic maps into a Henry gas solubility optimization algorithm (HGSO). The new algorithm is named chaotic Henry gas solubility optimization (CHGSO). The hybridization is aimed at enhancement of the convergence rate of the original Henry gas solubility optimizer for solving real-life engineering optimization problems. This hybridization provides a problem-independent optimization algorithm. The CHGSO performance is evaluated using various conventional constrained optimization problems, e.g., a welded beam problem and a cantilever beam problem. The performance of the CHGSO is investigated using both the manufacturing and diaphragm spring design problems taken from the automotive industry. The results obtained from using CHGSO for solving the various constrained test problems are compared with a number of established and newly invented metaheuristics, including an artificial bee colony algorithm, an ant colony algorithm, a cuckoo search algorithm, a salp swarm optimization algorithm, a grasshopper optimization algorithm, a mine blast algorithm, an ant lion optimizer, a gravitational search algorithm, a multi-verse optimizer, a Harris hawks optimization algorithm, and the original Henry gas solubility optimization algorithm. The results indicate that with selecting an appropriate chaotic map, the CHGSO is a robust optimization approach for obtaining the optimal variables in mechanical design and manufacturing optimization problems.

  相似文献   
867.
This paper introduces the development of a multimodal data visualisation system and its evaluations. This system is designed to improve blind and visually impaired peoples access to graphs and tables. Force feedback, synthesized speech and non-speech audio are utilised to present graphical data to blind people. Through the combination of haptic and audio representations, users can explore virtual graphs rendered by a computer. Various types of graphs and tables have been implemented, and a three-stage evaluation has been conducted. The experimental results have proven the usability of the system and the benefits of the multimodal approach. The paper presents the details of the development and experimental findings, as well as the changes of role of haptics in the evaluation.  相似文献   
868.
This paper argues that the current involvement of end users in the design of technological artefacts is too superficial. It is common to involve people in requirements generation, but rarely in product inception or design. A study is reported involving five households in central Scotland, who were each visited on three occasions, using a new investigative framework. Illustrative examples are provided of the strengths and weaknesses of the methods used. Despite the latter, it is demonstrated that the general public can both generate and critique design ideas and that valuable contributions to understanding people's relationships with technologies can be expected both from children and from the elderly. Electronic Publication  相似文献   
869.
The synthesis of programs as well as other synthetic tasks often end up with an unprovable, partially false conjecture. A successful subsequent synthesis attempt depends on determining why the conjecture is faulty and how it can be corrected. Hence, it is highly desirable to have an automated means for detecting and correcting faulty conjectures.We introduce a method for patching faulty conjectures. The method is based on abduction and performs its task during an attempt to prove a given conjecture. On input X. G(X), the method builds a definition for a corrective predicate, P(X), such that X. P(X) G(X) is a theorem. The synthesis of a corrective predicate is guided by the constructive principle of formulae as types, relating inference with computation.We take the construction of a corrective predicate as a program transformation task. The method consists of a collection of construction commands. A construction command is a small program that makes use of one or more program editing commands, geared towards building recursive, equational procedures.A synthesised corrective predicate is guaranteed to be correct, turning a faulty conjecture into a theorem. Whether conditional or not, it will be well-defined. If recursive, it will also be terminating.Our method is amenable to mechanisation, but careful search guidance is required for making a productive use of the failure of a proof. A failed proof attempt quickly yields a huge, possibly infinite, deduction tree, giving rise to exponentially many abductive explanations. We suggest that a proof planning approach can structure the task of correcting a formula in such a way as to allow significant automation, while dramatically restricting the search space.  相似文献   
870.
Some conditions relating to the automata involved in the W-testing method are discussed. It is also shown how to use the method for reduced automata instead of minimal automata. New design test conditions (weak output distinguishable, strong test-complete and output delimited type) are considered for the generalised stream X-machines (stream X-machines with basic functions replaced by relations and having as output strings of symbols rather than single symbols). It is proved that testing methods similar to those already developed for ordinary deterministic stream X-machines may be applied for generalised stream X-machines with output delimited types. A particular case of generalised stream X-machine with output delimited type is the X-machine with output delimiter, which produces outputs having a distinct right end character. Received October 2000 / Accepted in revised form January 2001  相似文献   
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